HP 21S Stat/Math Calculator from 1989

This video is about the HP 21S, a niche statistics and maths calculator from HP's Pioneer series.

Sections of this video:
0:00 - Intro
1:22 - Physical Design
3:21 - Basic Usage
4:46 - Probability Distribution Functions
8:23 - Statistics and Welford's Method
10:27 - Built-in Library
11:30 - Summary

For those that are interested in knowing more about how to disassemble an HP 20S or HP 21S check out Logan West's video here:
   • HP 20s Calculator Screen/Keyboard Repair  

For those that are interested in Welford's Method for calculating the mean and variance of normal distributions check out this link:
https://jonisalonen.com/2013/deriving...

For more calculator videos check out my channel:    / calculatorculture